PDA

View Full Version : Basics of * time pads by mikeE



DATA
05-09-2002, 03:20 AM
hi,


here goes..

Data.

-------------------------------------------------------------------------------------

MikeE writes: Introduction: Cryptography and Stenography are used in many more places that you may realize, yet is not used as much as it should be in some places. Wether you use these methods in your business, or your home, be sure to use good encryption. Not only does it ward off any onlookers, it will develop good habits in you.

The one time pad method was invented by the Russians, er, Soviet ***** during the Cold War. It is simple in method, but UNBREAKABLE if used RIGHT. First out, I will start off with what is used in this method:

- The one time pad itself. This is a pad of random numbers that has to be at least as long as your message text or
longer. If you plan on sending many messages, the best way is to make a longer pad, even if the messages will not
be sent often. See, in order for this method to work, BOTH PEOPLE have to have the same exact one time pad.
And if you make short pads, the more you will have to trade pads with the message receiver/sender and therefore
the more possible ways someone may find the pad (i.e. in a dead drop) or discover that that is the method of
encryption you are using. Also, all the numbers MUST be completely random. DO NOT use a computer to
generate these number, because computers still tend to follow paths and are not as random as the human mind.

-Your message to be encrypted. Remember the message cannot be longer than your pad. The Soviets had pads, all
with hundreds of numbers on a sheet, with hundreds of sheets in a pad.

-Pencil and paper

First, we must change all periods to and "x" In example, "Hello." becomes "Hellox" Also all signs like
"$", "&" "@" and such must be also changed to their respective word forms. Also spell out ALL numbers, i.e. ONE
THREE SIX NINE, etc.
Now for the method. Lets say the following is my Pad of random numbers:

*24* 85*2 **78 *576 2884 0582 *024 724* 0*84 2467 4824 0572 4**7

Your one time pad would be longer, but this is all we will need for our first message.
One good way to make a one time pad is to take a series of random letters, like
"ADHIWURTQMCKOKEZPLWIEUCNAOURSF" and use the key below to convert them into numbers. Split
them into groups of four for simplicity.

Now we must convert out letters to numbers. And type of key here can be used, but for simplicity lets go with this:

A=0* B=02 C=0* D=04 E=05 F=6 G=07 H=08 I=0* J=*0 K=** L=*2 M=** N=*4 O=*5 P=*6 Q=*7 R=*8 S=**
T=20 U=2* V=22 W=2* X=24 Y=25 Z=26

Simple enough, but it will still be an unbreakable code. Remember to use "0*" instead of "*" and so on or your
math will not come out right.

Now lets create our message, say:

"Meet me at Eleven."

This message must be formatted like so:
"MEET ME AT ELEVENX"

When coding the message, end the message with "XX" to signal termination of the message. If needed, add
additional X's to 'pad-out', or run out the current 4 digit number string.

Now to encrypt the message. First, change the letters to numbers:

**050520 **05 0*20 05*2052205*424

Then format into 4 digit phrases:

**05 0520 **05 0*20 05*2 0522 05*4 2424

Notice I added two X's at the end to signal termination. If this would not have come out even, I would have just
added more.

Now to encode the message. The numbers are added with Fibonacci Addition. Numbers ARE NOT carried over to
the next column. I.E. *2+7*=6*. You add left to right this way. Notice the first group of four numbers is not used
to encode the message. This is the start key, and when the message is received the person can tell by this un-
changed number where in his pad the message starts. So lets encode our string.

First is the pad numbers, then the message numbers. (I chopped off the un-needed numbers from our pad example.)

One time pad: *24* 85*2 **78 *576 2884 0582 *024 724* 0*84

Message: ---- **05 0520 **05 0*20 05*2 0522 05*4 2424

Result: *24* *8*7 *4*8 487* 2*04 00*4 *546 775* 25*8

Tada! You know have your encrypted message. Now the Soviets went a step further, and changed the above
numbers to letters again with a old radio number code at the time I believe (correct me if I am wrong). That is not
needed but again adds a bit of security.
To decrypt the message, do the same method but BACKWARD, using Fibonacci Subtraction. If you come upon
two numbers which would equal a negative, add ten to the first number, i.e. 4-* = (*0+4)-* = *4-* = 5. :

*24* *8*7 *4*8 487* 2*04 00*4 *546 775* 25*8

*24* 85*2 **78 *576 2884 0582 *024 724* 0*84

------ **05 0520 **05 0*20 05*2 0522 05*4 2424

Now we take the decrypted numbers and change them to their word form:
ME ET ME AT EL EV EN XX
Which Becomes:
MEET ME AT ELEVEN (message end)

Amazing isn't it? And it is UNBREAKABLE, if used RIGHT. This means the burning of ALL used up pads, and
NEVER EVER using a one time pad TWICE. This incenses the risk of someone figuring out the algorithm and
cracking your code. The CIA had a tremendously hard time cracking these codes in the **50's and 60's. The fact
was that they COULDN'T. Not until a British spook recovered a one time pad from a Soviet spook did someone
crack the code. And also, the Soviets were using the pads over again. They were recycling them, and this caused
some code breakers at CIA to find bits and pieces of words in the messages. Reusing pads takes the security percent
down DRASTICALLY. If re-used completely, your encryption goes from *00% to 0%.